docs: def convert_la_to_rgba(self, row, result):
          """Convert a grayscale image with alpha to RGBA."""
          for i in range(len(row) // 3):
              for j in range(3):
                  result[(4 * i) + j] = row[2 * i]
              result[(4 * i) + 3] = row[(2 * i) + 1]